Video conferencing is an established method of collaboration between remotely located participants. A video image of a remote environment is broadcast onto a local display allowing one or more participants at a local site to see and talk to one or more remotely located participants.
Some video conferencing applications seek to provide physically realistic eye contact between participants at remote sites. This can be referred to as “person-accurate” eye contact, “personalized” eye contact, consistent gaze, or correct gaze. However, it is currently difficult to place video cameras in a video conference situation at locations needed to achieve proper eye-contact, namely at or very near the eyes of each displayed participant. For example, typically within a video conference between two participants, a video camera at each site is located above a display device (e.g., plasma display) that is viewed by each participant, thereby resulting in a slightly awkward downward viewing angle of the other participant. As such, the correct gaze or proper eye contact between the two participants is not really achieved when employing this technique.
Another conventional two-party video conferencing technique involves the placement of a half-silvered mirror in front of a display screen that is viewed by each participant. For example, at each site, a half-silvered mirror can be positioned at a 45 degree angle and situated between the display screen and its participant. Additionally, a video camera is usually located at each site above the half-silvered mirror such that the principal axis of the camera is aligned with the preferred viewing direction of the display. This causes each participant to be looking into the camera while viewing the display, so that correct gaze can be achieved between the two participants. However, this technique is difficult to extend to systems employing multiple cameras at each site, large display surfaces, curved display surfaces, or combinations of these.
Yet another conventional video conferencing technique for trying to achieve correct gaze between two video conferencing participants involves using a hole within a display screen. For example, at each site, a video camera is positioned behind the display screen and aligned to operate through the hole in the display screen. Note that the hole through the display screen is typically located such that it is not distracting to the participant viewing the images shown on the screen. For instance, the hole may be located in a part of the screen where a black region will be projected onto the screen. However, the problem with this technique is that the proper eye contact or correct gaze between the two participants is not really achieved, since the hole is typically not located where the eyes of the remote participant are displayed. Furthermore, it is often difficult to conceal the hole so that is does not detract significantly from the displayed image.
Therefore, it is desirable to address one or more of the above issues.